Bite-finder.



L. A. SMITH. BITE FINDER. APPLICATION FILED JULY 28. I915.

Patented July 25, 1916.

ATTORNEYS BITE-FINDER.

Specification of Letters Patent.

Patented July 25, 1916.

Application filed July 28, 1915. Serial No. 42,446.

To all whom it may concern:

Be it known that I, LAWRENCE A. SMITH, a citizen of the United States, and a resident of Port Gibson, in the county of Claiborne and State of Mississippi, have invented certain new and useful. Improvements in Bite-Finders, of which the follow ing is a specification.

My invention is an improvement in bite finders, and the invention has for its object to provide a device of the character specified, for indicating by the contraction of the temporal muscles when the lower jaw is properly placed and in its natural closed position with respect to the upper jaw, that is, to indicate the proper occlusion of the teeth.

In the drawings: Figure 1 is a side view of the improved device in use; Fig. 2 is a front view on an enlarged scale; Fig. 3 is a side view of Fig. 2, and Figs. a and 5 are enlarged sections on the lines 4% and 5-5 respectively, of Fig. 2.

The present embodiment of the invention consists of an arch or yoke-shaped frame, comprising a body. 1 and arms 2 extending from the ends of the body at approximately aright angle with respect to each other, and a species of shoe or casing 3 is mounted on the body of the frame at the center thereof, and is held in place in any suitable or desired manner. This shoe or casing is a tubular casing and of rectangular cross section, and fits closely around the body, forming a support for a plate 1 which is secured to the front face of the casing 3. This plate 4 is segmental, being slightly more than a half circle, and the rounded edge of the plate has a plurality of scales 5 and 5 respectively, the scales extending from the center of the curved edge to each end of the said edge, and the graduations of the scale are numbered from 0 to 5 respectively.

A pair of indicators 6 and 6* cooperate with the scale, the said indicators being pivoted at the center upon which the curved side or edge of the plate is formed, on a pivot pin or screw 7", and the lower ends of the indicators are pointed as shown, to register with the graduations on the scale, and each indicator cooperates with one of the scales, the indicator 6 cooperating with the scale 5, while the indicator 6 cooperates with the scale 5. Each of the indicators 6 and .6 has a series of teeth forming a mutilated pinion 7 and 7 respectively, at its upper end, and the teeth of each lndicator are concentric with the pivot pin or screw 5 upon which the indicators swing. A rack bar S8 cooperates with each indicator, each rack bar having teeth on its under edge and at its innerend, meshing with the pinion 7 or 7 as the case may be, of the adjacent indicator.

Levers 9 and 9 are pivoted to the arms 2 of the frame, each lever being pivoted near its lower end to the lower end of the adjacent arm, by means of a screw 10 or the like, and the upper ends of the levers are connected with the rack bars 8 and 8, the lever 9 being pivoted to the rack bar 8, while the lever 9 is pivoted to the rack bar 8.

A guide loop 11 is secured to each arm near its junction with the body 1 of the frame, and each loop 11 incloses the adjacent lever to limit the movement thereof on its pivotal connection. The loops thus act not only as guides to hold the levers close to the arms, but in addition act as stops to limit the swinging movement of the levers.

A U-shaped guide or holder 12 is arranged above the toothed ends of the rack bars 8 and 8 the said holder or guide being supported by the pivot pin 7 which pivots the indicators to the casing 2. The guide 12 has a depending spacing member 13 which depends between the rack bars 8 and 8, thus spacing the said bars, and the spacing member also depends between theupper ends of the indicators 6 and 6, thus spacing also the indicators. This spacing member 13 has an opening through which passes the pivot pin 7 Limiting blocks 14, of rubber or like resilient material, are arranged in the holding member 12, between the side walls thereof and the spacing member 13 and adjacent to the body, and these limiting blocks limit the upward movement of the rack bars, so that theycannot become accidentally disengaged. These blocks, however, are intended to yield in order to permit the rack bars to move out of contact with the teeth of the pinion when desired. That is, by pressing upward on the bars, the limiting blocks will yield to permit the teeth of the rack bars to disengage from the teeth of the pinions, to permit the rack bars to be adjusted with respect to the pinions, under conditions to be later described.

be held in adjusted position by means of the set screws.

Each bar is provided at its inner end with a head 18, formed from wire or the like,

bent to the shape shown in Fig. 3. It will be understood that these heads are not necessarily ofthe shape shown, being preferably, however, of openwork, in order that they will adhere to the skin of the person upon whom they are used, and will not slip laterally easily on the head.

A wing or vane 19 is connected with each of the arms 2, the said wings or vanes being adapted to engage the head of the person upon which the finder is used, to steady the frame, and to hold it in upright position. Each of thesewings or vanes is curved longitudinally as shown, and is of greater width at its free end, gradually decreasing in width toward the attached end, and they are arranged with their convex faces adjacent. Each wing is provided at its small end with a species of casing 20 of cylindrical form, and each casing has its outer end provided with clutch teeth 21. Each casing is also provided with a transverse diaphragm 22 near its inner end, and the diaphragm has a central opening for receiving a pin or bolt 23 extending axially from a hub or clutch section 24, which is secured to the rear face of the adjacent arm 2 by means of rivets or the like, as shown in Fig. 1. This hub or clutch section is cylindrical and has teeth cooperating with the teeth 21 of the casing 20. I

The pin 23, as before stated, extends axially from the hub 24, passing through the central opening of the diaphragm 22, into the body of the casing 20.. A coil spring 25 encircles the pin between the diaphragm and a fixed stop 26 adjustable on the pin. This stop in the present instance comprises a washer and a nut, the nut being threaded onto the pin in such manner that the tension of the spring may be varied, and in such manner that the clutch teeth 21 may be disengaged from the teeth of the hub 24, to permit the wing 19 to be adjusted.

The teeth 21 and the cooperating teeth of the hub are ratchet teeth, as shown, so arranged that while the wing or vane may be swung freely toward the other wing or vane it cannot swing in the opposite direction.

VVhenthe wing or vane is swung toward the opposite wing or vane, the teeth slip idly over each other, but they prevent movement away from the head.

The levers 9 and 9 are normally held in parallelism and in vertical position by means of plate spring 26. Each of these springs is secured to the rear face of the adjacent arm 2, as indicated at 27, and at two points in the length of the spring, and the lower free end of the spring is offset inwardly and engages the shoe 15 of the adjacent lever 9 or 9 as the case may be, to hold the lever in normally upright or vertical position.

In operation, the device is placed on the head of the patient, in the manner shown in Figs. 1 and 2, with the heads 18 of the de vice resting just above the body of the temporal muscle at each side, and in position to be aflected by the contraction of the muscle. As is known, it is very difficult to ascertain when perfect occlusion occurs. The condyles of the lower jaw have a considerable movement in the glenoid fossae, and I have discovered that the temporal muscles do not simultaneously contract except when the occlusion of the teeth is perfect. As is known, it. is impossible to correctly articulate a set of teeth in bridge work or plate work, without having a perfect bite from which to work, and that the perfect bite cannot be obtained except when there is perfect occlusion. The purpose of the present device is to indicate beyond question and without depending upon the patient or upon the operator to determine this point. As before stated, the device is arranged with the heads 18 resting directly above the bodies of the temporal muscles, so that when these muscles contract in moving the condyles into the glenoid fossaa, the bars 16 and the heads 18 will be moved outwardly away from each other against the resistance of the springs 26.

The device is adjusted to the head by means of the bars 16, and by means of the yielding blocks 14:. The device is arranged in the manner shown in Fig. 2, that is, with the heads 18 bearing against the bodies of I the temporal muscles, with the levers 9 and 9 as nearly vertical and parallel as may be and with the indicators 6 and 6 at Zero on the scales 5 and 5. When this relation is attained, the rack bars are droppedinto engagement with the pinions, that is, if it has been necessary to disengage them in adjusting them. In adjusting to various widths of head, the bar 16 may be moved in the shoe and if the adjustment is enough to disturb the relation of the indicators 6 and 6 with respect to the scales 5 and 5*, it will be understood that the rack bar will be released to permit the indicators to take zero position, after which the rack bars are again engaged with the pinions. The wings or vanes are moved into engagement with the Figs. 1 and 2, and they are held in this position by the clutch teeth. With the uprights arranged as above specified the patient will manipulate the lower jaw, until the heads 18 are moved away from each other by the contraction of the temple muscles. This movement will be indicated on the scale 5 and 5 and the operator will be able to determine by the relative movement of the pointers whether or not the contraction indicates perfect occlusion.

It will be understood that several bites will be taken, and the results compared with each other will be the determining factor. Unless the temporal muscles are contracted, the indicators will not be moved to any appreciable extent, so that the operator has a certain sure guide that will indicate to him the movement of the condyles into the glenoid fossae, and thus perfect occulsion. It will be understood that the device is used with bite plates.

I claim 1. A device of the character specified, comprising a yoke-shaped frame consisting of a body adapted to be arranged transversely of the head of the patient, and arms depending from the ends of the body, a lever pivoted to each arm near the lower end of the lever and at the lower end of the arm, each lever having a shoe at its lower end transverse to the long axis of the lever, a bar movable through each shoe and provided at its inner end with a head, a set screw threaded through each shoe and engaging the adjacent bar to hold the bar in adjusted position, a plate of segmental form connccted to the body at the center thereof, and with its curved edge downward, said plate having scales at its curved edge extending from the center of the edge in opposite directions, a pair of indicators pivoted to the center of the plate and having teeth concentric with their pivotal connection and designed to cooperate with the scales, a rack bar pivoted to each lever at the upper end thereof and engaging the teeth of one of the indicators, resilient means for holding each rack bar in engagement with the teeth, a spring normally holding each lever in vertical position and parallel with the other lever, and means connected with each arm and adjustable transversely thereof for engaging the head of the person operated upon to make counter-pressure against the opposite spring and to steady the frame.

2. A device of the character specified, comprising a yoke-shaped frame consisting of a body adapted to be arranged transversely of the head of the patient, and arms depending from the ends of the body, a lever pivoted to each arm near the lower end of the lever and at the lower end of the arm, each lever having a shoe at its lower end transverse to the long axis, of the lever, a

bar movable through each shoe and provided at its inner end with a head, a set screw threaded through each shoe and engaging the adjacent bar to hold the bar in adjusted position, a plate of segmental form connected to the body at the center thereof, and with its curved edge downward, said plate having scales at its curved edge eX- tending from the center of the edge in opposite directions, a pair of indicators pivoted to the center of the plate and having teeth concentric with their pivotal connection and designed to cooperate with the scales, a rack bar pivoted to each lever at the upper end thereof and engaging the teeth of one of the indicators, resilient means for holding each rack bar in engagement with the teeth, and a. spring normally holding each lever in vertical position and parallel with the other lever.

3. A device of the character specified, comprising a substantially U-shaped frame comprising a body and arms extending laterally therefrom, a pair of indicators pivoted to the body of the frame at the center thereof, each indicator having teeth concentric with its pivotal connection, a lever pivoted to each arm of the frame, a rack bar pivoted to the upper end of each lever and engaging the teeth of one of the indicators, a head connected with the lower end of each lever and adjustable transversely thereof, yielding means for holding the rack bars in engagement with the teeth, springs normally holding the levers in parallelism and in vertical position, and means in connection with each arm of the frame for engaging the side of the head of the patient to make counterpressure against the spring of the opposite lever and to assist in holding the frame in vertical position.

4. A device of the character specified, comprising a substantially U.-shaped frame comprising a body and arms extending laterally therefrom, a pair of indicators pivoted to the body of the frame at the center thereof each indicator having teeth concentric with its pivotal connection, a lever pivoted to each arm of the frame, a rack bar pivoted to the upper end of each lever and engaging the teeth of one of the indicators, a head connected with the lower end of each lever and adjustable transversely thereof, yielding means for holding the rack bars in engagement with the teeth, and springs normally holding the levers in parallelism and in vertical position.

5. A device of the character specified, comprising a substantially U-shaped frame adapted to fit over the head of the patient, a pair of indicators pivoted at the center of the frame and depending from their pivotal connection, a lever pivoted on each end of the frame and provided with a head at its lower end adjustable transversely of the frame, means detachably connecting the upper end of each lever and one of the indicators, for swinging the indicator in the opposite direction to the movement of the upper end of the lever, a spring normally holding each lever in vertical position, and means connected with each arm of the frame and adjustable toward and from the head for making counter-pressure against the spring of the opposite lever, each of the said means comprising a wing or Valle for engaging the head of the patient, means connecting each wing and the adjacent arm for permitting the wing to swing away from the arm toward the head of the patient and for preventing reverse movement olfflthe wing, said connection being detacha e.

6. A device of the character specified, comprising a substantially U-shaped frame adapted to fit over the head of the patient, a pair of indicators pivoted at the center of the frame and depending from their pivotal connection, a lever pivoted on each end of the frame and provided with a head at its lower end adjustable transversely of the frame, and means detachably connecting the upper end of each lever and one of the indicators, for swinging the indicator in the opposite direction to the movement of the upper end of the lever, a spring normally holding each lever in vertical position, and means connected with each arm of the frame and adjustable toward and from the head for making counter-pressure against the sprin of the opposite lever.

7 device of the character specified, comprising a substantially U-shaped frame adapted to fit over the head of the patient, a pair of indicators pivoted at the center of the frame and depending from their pivotal connection, a lever pivoted on each end of the frame and provided with a head at its lower end adjustable transversely of the frame, and means detachably connecting the upper end. of each lever and one of the indicators, for swinging the indicatorrin the opposite direction to the movement of the upper. end of the lever.

8. A device of the character specified,

comprising a frame adapted to fit on the head of the patient and having means for holding the frame transversely of the head, means slidably connected with the frame at each side thereof and adapted to engage the temple of the patient and to be moved outward by the contraction of the temporal muscles, springs normally pressing the said meansinward,an indicating mechanism on the frame for each of the said means, and connected therewith to indicate the extent of outward movement of the said means.

LAWRENCE A. SMITH.

Copies of thispatent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. I 

